Patent US3581499A successfully refreshed from Google Patents.
US3581499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Quick raise adapter
Assignee: McNeil Corp
•
Filing: 1969-05-09
•
Granted: 1971-06-01
•
Expires: 1989-05-09
Abstract
Abstract A U-shaped annular cup is disposed in a flow passage between the ram and center tube of a two speed hydraulic jack and acts as a seal during the pumping cycle and as a one-way valve during the release cycle which connects the pressure end of the ram to the reservoir via the center tube.
Inventors
- 👤 John M Barosko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:07
CPC Classifications
B; B66; B66F; B66F3/00; B66F3/24; B66F3/25; B66F3/42
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
196 words
In a hydraulic force applying device, means providing a working chamber and a reservoir for hydraulic liquid, a ram member movable in the working chamber and having a pressure end defining a pressure chamber within the working chamber, an aperture terminating within the ram member and opening into the pressure chamber out of the pressure end, a fixed position tube member within the aperture and opening at one end into the aperture and having a second open end, said tube being smaller than the aperture to provide a flow passage between the tube and the wall of the aperture, hydraulic pumping and circuit means connected to the reservoir for pumping and delivering hydraulic liquid under pressure to the second end of the tube and to the pressure chamber and including release valve and passage means for selectively connecting the second end of the tube to the reservoir, and one-way seal means on one of said members and engaging the other and operated by pumping pressure to seal off said flow passage, said seal means being movable to open said flow passage when the pressure in said pressure chamber substantially exceeds the pressure in the tube member.
Claim 2
Dependent Claim
196 words
In a hydraulic force applying device, means providing a working chamber and a reservoir for hydraulic liquid, a ram member movable in the working chamber and having a pressure end defining a pressure chamber within the working chamber, an aperture terminating within the ram member and opening into the pressure chamber out of the pressure end, a fixed position tube member within the aperture and opening at one end into the aperture and having a second open end, said tube being smaller than the aperture to provide a flow passage between the tube and the wall of the aperture, hydraulic pumping and circuit means connected to the reservoir for pumping and delivering hydraulic liquid under pressure to the second end of the tube and to the pressure chamber and including release valve and passage means for selectively connecting the second end of the tube to the reservoir, and one-way seal means on one of said members and engaging the other and operated by pumping pressure to seal off said flow passage, said seal means being movable to open said flow passage when the pressure in said pressure chamber substantially exceeds the pressure in the tube member.
Claim 3
Dependent Claim
60 words
A device as set forth in claim 1 wherein said seal means includes a retainer attached to one of the members and a U-shaped resilient seal element supported on the retainer and having a lip resiliently engaging the other of the members to seal off said flow passage, the lips of the U-shaped seal extending away from said pressure chamber.
Claim 4
Dependent Claim
22 words
A device as set forth in claim 2 wherein said seal means is attached to the ram member adjacent its pressure end.
Claim 5
Dependent Claim
22 words
A device as set forth in claim 2 wherein said seal means is attached to said tube member adjacent said one end.
Claim 6
Dependent Claim
144 words
In a two speed hydraulic jack, an elongated longitudinally movable ram member having a pressure receiving end and an internal bore opening out of said end, a tube member extending inside said bore and having an opening into said bore but spaced from the wall thereof to provide a flow passage connecting the pressure end with the tube member opening, means for selectively connecting the inside of the tube to a source of hydraulic liquid at pumping pressures and to a hydraulic liquid reservoir, means for connecting the pressure end of the ram member to a source of hydraulic liquid at pumping pressures, and a combination seal and one-way valve means in said flow passage to seal it against hydraulic liquid flow from the tube member to the pressure end but provide for hydraulic liquid flow from the pressure end to the tube member.
Claim 7
Dependent Claim
144 words
In a two speed hydraulic jack, an elongated longitudinally movable ram member having a pressure receiving end and an internal bore opening out of said end, a tube member extending inside said bore and having an opening into said bore but spaced from the wall thereof to provide a flow passage connecting the pressure end with the tube member opening, means for selectively connecting the inside of the tube to a source of hydraulic liquid at pumping pressures and to a hydraulic liquid reservoir, means for connecting the pressure end of the ram member to a source of hydraulic liquid at pumping pressures, and a combination seal and one-way valve means in said flow passage to seal it against hydraulic liquid flow from the tube member to the pressure end but provide for hydraulic liquid flow from the pressure end to the tube member.
Claim 8
Dependent Claim
54 words
A device as set forth in claim 1 wherein said seal means comprises a U-shaped resilient seal element supported by one of the members and having a lip resiliently engaging the other of the members to seal off said flow passage, the lips of the U-shaped seal element extending away from said pressure chamber.
Claim 9
Dependent Claim
73 words
In a hydraulic jack, a movable ram having a high speed face and A low speed face and a flow passage connecting the faces, and a U-shaped resilient seal member in said passage providing resilient valve and seal means in said passage and acting to prevent flow of hydraulic liquid from the high speed face to the low speed face but permitting flow from the low speed face to the high speed face.
Claim 10
Dependent Claim
73 words
In a hydraulic jack, a movable ram having a high speed face and A low speed face and a flow passage connecting the faces, and a U-shaped resilient seal member in said passage providing resilient valve and seal means in said passage and acting to prevent flow of hydraulic liquid from the high speed face to the low speed face but permitting flow from the low speed face to the high speed face.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-31 | 1974-11-30 | 1975-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-31 | 1978-11-30 | 1979-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-31 | 1982-11-30 | 1983-06-01 | $7700.00 | Window Closed / Lapsed |